In utero cleft palate repair in the ovine model

Cleft lip and palate defects assume many forms from mild to severe, but all may be associated with abnormal craniofacial development. Even the most expert and sophisticated methods of surgical repair are followed by scar contraction and fibrosis, which result in skeletal defects, dental abnormalities, cosmetic disfigurement, and speech impairment. Recent clinical and experimental observations that fetal cutaneous wounds heal without scarring are of great potential interest in the management of cleft lip and palate. The objective of this study was to investigate the effect of prenatal repair of iatrogenically produced cleft palate on scar formation in the fetal lamb model. Ten ewes were operated on ranging in gestation from 70 to 133 days. Fifteen lambs were studied (nine cleft palates produced and repaired in utero; one cleft produced in utero and not repaired, four normal, unoperated palates; and one cleft palate produced and repaired 1 week postnatally). The lambs were delivered normally at 145 to 147 days gestation and maintained with the ewe until 1 month of age. The lambs were euthanized, and the surgical area of the palates studied grossly and histologically. Animals operated at 112 days or later in gestation exhibited scars both clinically and histologically. The animals that had cleft palate produced and repaired at 70 days gestation did not have a visible palatal scar at 1 month of age. Histologically, there was evidence of minimal scarring without disruption of normal architecture. Studies are underway to determine the impact of reduced scarring on craniofacial growth after palatal repair during mid gestation in the ovine model.